Slide switch



Feb. 9, 1960 R. s. STONE ETAL SLIDE SWITCH 2 Sheets-Sheet 1 Filed June 24, 1957 I INVENTORSI RICHARD s. STONE FORREST R. WOLF mg 2 Z ATT'YS .Feb. 9, 1960 R. s. STONE ETAL 2,924,691

SLIDE SWITCH Filed June 24, 1957 2 Sheets-Sheet 2 FIG. 4 ll I4 22 26 271 a I ZJQLL LL L LA I QE'E -k\w my, .:-HH l\ d ,H ulllmw L FIGS new! 4 INVENTORS. RICHARD S. STON E FORREST R. WOLF BY g ATT'YS United States Patent SLIDE SWITCH Richard S. Stone, Chicago, and Forrest R. Wolf, Arlington Heights, 111., assignors to Anderson Controls, Inc., Des Plaines, 11]., a corporation of Illinois Application June 24, 1957, Serial No. 667,362

10 Claims. (Cl. 200-153) This invention relates to a slide switch, and more especially to a switch having a slidable snap contact alternately engageable with separate stationary contacts when reciprocated from end to end of its range of movement.

Itis an object of the invention to provide a slide switch'structure which is functional to selectively complete alternate circuits. Another object of the invention is in the provision of a slide switch of novel construction, and having advantages that afiord superior operating characteristics over prior art switches.

Still another object is in providing a slide switch wherein the rate of actual switching movement between contacts is independent of the rate at which the slidable elements of the switch are moved from one position to another. Yet another object of this invention is to pro vide a slide switch structure having a snap-contact action so that one circuit is interrupted and another completed rapidly and simultaneously, whereby arcing is minimized and the life of the switch prolonged.

Still a further object is in the provision of a snap switch having fixed, elongated contacts arranged in spaced, parallel pairs, and a slidable snap contact reciprocable along the length of the fixed contacts and in selective alternate engagement therewith, whereby the snap contact is continuously cleaned and polished during use of the switch; and wherein an over-center snap action is incorporated to eifectuate movement of the snap contact between the fixed contacts selectively engaged thereby. Additional objects and advantages will become apparent as the specification develops.

An embodiment of the invention is illustrated in the accompanying drawings, in which Figure 1 is a broken perspective view of the slide switch structure, showing the snap contact thereof in one of its alternate positions Figure 2 is a broken perspective view, showing the snap contact in the other of its alternate positions; Figure 3 is a broken, enlarged perspective view of the snap contact assembly; Figure 4 is a longitudinal sectional view of the switch structure; Figure 5 is a horizontal sectional view taken .along the line 5-5 of Figure 4; Figure 6 is a horizontal sectional view taken along the line 6-6 of Figure 4; and Figure 7 is a transverse sectional view taken along the line 77 of Figure 4.

In describing the details of the structure, reference will first be made to Figures 1 through 3 in particular which show that the switch includes a frame or housing 10 having upper and lower separable sections 11 and 12 that are secured together by a plurality of pins 13. The frame sections 11 and 12, as is evident from Figure 4, define a generally rectangular channel or compartment 14 interiorly thereof, and are made of a plastic or other electrical insulating material.

Mounted within the compartment 14 are two sets of fixed or stationary contacts that are identified, respectively, with the numerals 15--16 and 17-18. contacts 15 and 17 are secured by any suitable means ice to the upper frame section 11; and similarly, the contacts 16 and 18 are secured to and carried by the lower frame section 12. The contacts are elongated and extend along the longitudinal axis of the frame 10, and are oriented so that the contacts 15 and 16 are in spaced apart, parallel relation one above the other; and in an identical manner, the contacts 17 and 18 are arranged one above the other in spaced apart, parallel relation.

Each of the fixed, elongated contacts is provided at an end thereof with an inclined shoulder or cam surface, and such surfaces are denoted with the numerals 19 through 22. The contacts 15 and 17 are in planar alignment, and the cam surfaces 19 and 21 thereof are at the same or corresponding ends and incline downwardly toward the contacts 16 and 18. The contacts 16 and 18 are also in planar alignment, and the cam surfaces 2!] and 22 thereof are at the same ends and incline upwardly toward the contacts 15 and 17. It is apparent that the cam surfaces 19 and 21 and cam surfaces 20 and 22 are at opposite ends of the compartment 14. All of the contacts are formed of silver or other electrical conducting material.

Slidably mounted for longitudinal movement from end to end of the compartment 14 is a snap contact assembly identified in its entirety with the numeral 23. assembly comprises a carrier or mounting block 24, formed of a non-conductive material having a flat, horizontal wall 25 and end walls 26 and 27 which extend upwardly therefrom in spaced apart relation. Extending into and anchored to the mounting block 24 are a pair of push rods 28 and 29 that, as shown in Figure 4, have threaded inner end portions which are threadedly received within tapped openings therefor within the member 24. The rods s'lidably extend through openings 30 and 31 provided therefor in the end walls of the lower frame section 12 (Figure 4), and these rods are adapted to be secured to mechanism which is not shown which will function to reciprocate the mounting block 24, first in one longtiudinal direction within the compartment 14 and then in the other direction. It will be apparent that various arrangements may be employed for securing the rods 28 and 29 to the block 24.

Secured to the base wall 25 of the mounting member 24 by means of a rivet 32 is a bracket 33 of generally U-shaped configuration, and therefore having upwardly extending legs 34 and 35 arranged in spaced, parallel relation-each of which has an arcuate upper end that turns outwardly to define spring seats 36 and 37. Extending about the bracket 33 is a snap contact 38 that is severed centrally, and with portions removed therefrom, to define spaced legs 39 and 40 that are integrally connected at their ends (as shown at 41 and 42). Spring tongues 43 and 44 are defined within the dimensional limits of the legs 39 and 40, and are seen to engage at their respective inner ends the spring seats 36 and 37 of the bracket 33. The tongues 43 and 44 are cut or formed so as to have a length slightly greater than the distance between the spring seats and the respective ends 41 and 42 of the snap contact so as to exert a continuous biasing force against those ends, whereupon they are resiliently urged into engagement with the contacts 16 and 18, or alternately with the contacts 15 and 17.

The spring tongues 43 and 44 have an over-center action so that the snap contact has two stable positions, one of which is shown in Figure 3 wherein the respectiveends 41 and 42 thereof are resiliently urged toward the contacts 16 and 18, and the other is shown in Figure 2 wherein they are biased into engagement with the upper contacts 15 and 17. It will be evident that the spacing between the overlying contacts 15 16 and 17-18 mustbe' sufficient so as to permit such alternate movement of Patented Feb. 9, 1960,

-2,9a,4,e91 I p h the snap contact into either of its stable positions. The snap contact may be made of thin spring metal, and is preferably provided with contact buttons or terminals 45 and 46 at the ends thereof (as shown in Figure 3), and it will be understood that these buttons or terminals have identical counterparts along the underside of the snap contact which will actually engage the fixed contacts 16 and 18.

The four fixed contacts must be electrically connected in a circuit or circuits controlled by the switch, and such connections may be effected in any coventional manner, such as by means of the terminals 47 through 50 which are connected thereto by rivets or otherwise. These terminals are shown in Figures 5 and 6, but have been omitted from the other figures for the purpose of clarity. It should be noted that the terminals 47 and 48 (and therefore the upper contacts 15 and 17)' will be connected in the same circuit, while the terminals 49 and 50 and their fixed contacts 16 and 18 will provide a separate switch circuit. Consequently, the snap contact 38 will selectively perform a switching function completing either of such circuits.

Operation In describing the operation of the switch structure, the snap contact 38 may be assumed to be in engagement at the respective ends thereof either with the contacts 15 and 17 or 16 and 18, since it has two stable positions of alternate engagement therewith. For convenience, the position shown in Figure 1 will be considered initially. The entire snap cont act assembly 23 is at the extreme right-hand limit of its reciprocatory motion, having been moved there either by a pushing force exerted thereon by the rod 29 or a corresponding pulling force applied thereto through the rod 28. The snap contact 38 is in its dovm position, with the ends thereof engaging the lower fixed contacts 16 and 18.

The assembly 23 will remain in the position shown in Figure 1 until a force is imparted thereto through the rods 28 and 29 that cause it to move toward the left and ultimately into the position shown in Figure 2. During the entire period of movement of the assembly 23 toward the left, the snap contact 38 will remain in engagement with the lower fixed contacts 16 and 18. As the assembly moves toward the left, it will approach the position shown in Figure 3 wherein the ends 4-1 and 42 are nearing the upwardly inclined cam surfaces 20 and 22. When the ends of the snap contact reach the cam surfaces and ride upwardly thereon, the ends 41 and 42 are ultimately forced over-centerthat is, above the plane defined by the spring seats 36 and 37. At such time, the spring tongues 43 and 44 (because of the resilient force exerted thereby on the ends 41 and 42 of the contact 38) snap the ends away from the contacts 16 and 18 and into engagement with the fixed contacts 15 and 17 thereabove.

' This latter position is shown in Figure 2, and the snap action occurs when the assembly 23 is adjacent the limit of its reciprocatory stroke toward the left of the frame 10. More particularly, as is revealed from an inspection of Figure 4, the snap action occurs when the ends of the contact 38 reach the upper level of the cam surfaces 20 and 22 since such level is slightly above the midpoint or center plane defined by the spring seats 36 and 37. The snap contact will remain in this position, wherein it forms a circuit between the upper contacts 15 and 17, until the assembly 23 has been reciprocated to the opposite end of the compartment 14- and into the position shown in Figure 1. During this reciprocatory stroke, a reverse action occurs as the ends of the snap contact ride downwardly along the cam surfaces 19 and 21 and into an over-center position, at which time they are snapped from engagement with the upper fixed contacts and into engagement with the lower fixed contacts. The same relation exists between the lower limit of the cam sur- '4 faces 19 and 21 and the center plane of the snap contact, as described with reference to the cam surfaces 20 and 22.

It will be apparent that the rate of movement of the snap contact 38 into engagement with either the upper fixed contacts 15 and 17 or lower contacts 16 and 18 is 'wholly independent of the rate of movement of the assembly 23, and is related only to the spring characteristics of the contact 38. The snap action of the contact 38 is quite rapid, whereupon there is but a momentary interruption in switching from one set of contacts to the other; and because of the rapid action, arcing is minimized whereby the contacts have a long life. Further, in sliding along the entire length of the respective fixed contacts, the terminals or buttons 45 and 46 and their counterparts are self-cleaning, which also increases their effective useful life.

It will be appreciated that a number of additional advantages accrue from the switch construction described. For example, controlled linear motion of the rods 28 and 29 (or, more particularly, of the snap switch carried thereby) aifords control over the programming of a sequence of events. An exemplification of such programming would be that of having the switch operate one sequence of events when reciprocated in one direction, and to operate a completely different sequence of events when reciprocated in the opposite direction.

This result may be achieved in several ways, one of which would be to equip the elongated contacts with a plurality of cam surfaces so that the snap switch would be shifted between the upper and lower elongated contacts several times during linear movement thereof in one direction. It is apparent that such cam surfaces provided respectively by the upper and lower elongated contacts need not be equal in number. Further, the contacts could beprovided with cam surfaces only intermediate the endsthereof.

Another manner of accomplishing sequence programming would be to interrupt the continuity of the elongated contacts so that as the snap switch is moved longitudinally therealong, points are encountered at which no electrical connection is established with the elongated contacts. Also, the elongated contacts could have several interrupted segments, and the various segments connected to different circuits. In effect then, each of the elongated contacts could provide a multiplicity of separate circuit connections. The invention has the additional advantage of switching circuits by means of linear motlon actuation, where formerly the same switching action was possible only by converting linear to rotary motion.

While in the foregoing specification an embodiment of the invention has been described in considerable detail for purposes of illustration, it will be apparent to those skilled in the art that numerous changes may be made in those details without departing from the spirit and scope of the invention.

We claim:

1. in a slide switch structure, a pair of continuously energized elongated contacts fixed in spaced apart, parallel relation, said contacts each having a cam surface therealong inclining toward the other of the contacts, a snap contact assembly mounted for slidable movement longitudinally along said elongated contacts and having terminals oriented for selective slidable engagement with the elongated contacts, said snap contact assembly havmg a spring tongue anchored adjacent an end thereof for over-center movement to urge said snap contact assembly into one of its two stable positions for selective engagement of said terminals thereof with said elongated contacts, and means for so moving said snap contact assembly to cause each of said terminals to alternately ride over the respective cam surfaces thereby forcing said spring tongue over-center to snap the then disengaged terminal into engagement with the elongated contact therefor.

2. In a slide switch of the character described, a housing defining an elongated compartment therein, a pair of elongated contacts fixedly carried by said housing in spaced apart, parallel relation, said contacts having therealong cam surfaces each inclining toward the other of the contacts, a snap switch assembly mounted within said compartment for slidable reciprocatory movement along the longitudinally extending axes of said fixed contacts, means for reciprocating said assembly, and a snap contact carried by said assembly and having a terminalequipped end thereof interposed between said fixed contacts, said snap contact having a spring tongue anchored adjacent an end thereof for over-center movement to selectively snap the terminal-equipped end of said snap contact into alternate engagement with said fixed contacts, said cam surfaces being oriented to effectuate such over-center movement of said spring tongue when the terminal-equipped end of said snap contact rides thereover in wiping along the respective fixed contacts.

3. The switch structure of claim 2 in which said assembly comprises a mounting block and a bracket carried thereby, said bracket having a spring seat receiving the aforesaid end of said spring tongue to anchor the same.

4. The switch structure of claim 2 in which an addi tional, substantially identical pair of elongated contacts are fixedly mounted within said housing and are respectively oriented in planar alignment with the aforesaid pair of elongated contacts, and in which said snap contact is provided with a second terminal-equipped end interposed between said additional pair of fixed contacts and also with an additional spring tongue anchored adjacent an end thereof for over-center movement to selectively urge said second terminal-equipped end into alternate engagement with said additional fixed contacts.

5. In a slide switch structure having spaced apart upper and lower fixed, elongated contacts, a snap contact assembly mounted for reciprocatory movement along the longitudinal axes of said fixed contacts, said assembly comprising a mounting block, a bracket carried by said mounting block and providing a pair of spring seats, a snap contact having end portions thereof interposed between said fixed contacts for selective engagement with the respective upper and lower ones thereof to wipe therealong during reciprocation of said assembly, a pair of spring tongues provided by said snap contact and having ends thereof respectively engaged within said spring seats and providing an over-center action to snap the end portions of said spring contact into selective engagement with the respective upper or lower fixed contacts, and means for shifting said spring tongues overcenter in alternate opposite directions to effectuate such snap action.

6. The switch structure of claim 5 in which the means for effectuating said over-center action comprises cam surfaces provided by the respective fixed contacts.

7. The switch structure of claim 6 in which means are provided to reciprocate said assembly to move the ends of said snap contact over said cam surfaces, and in which said last mentioned means comprises rod means secured to said assembly and extending along the reciprocatory axis thereof for imparting axially directed forces thereto.

8. The switch structure of claim 5 in which said spring seats are oriented in spaced apart relation.

9. In a switch structure of the character described, a housing, a pair of upper contacts and a pair of lower contacts, said contacts being elongated and fixedly mounted within said housing in paired, facing relation spaced from each other, said upper contacts having downwardly inclined cam surfaces adjacent the corresponding ends thereof, said lower contacts having upwardly inclined cam surfaces adjacent the opposite corresponding ends thereof, a snap contact assembly mounted within said housing for reciprocatory movement along the longitudinal extent of said contacts and having a snap contact with ends thereof disposed between the facing pairs of said upper and lower contacts, said ends being operative to alternately snap upwardly and into engagement with said upper contacts when moved over the cam surfaces of said lower contacts and to similarly snap downwardly into engagement with the lower contacts when moved over the cam surfaces of said upper contacts, and means for reciprocating said assembly to slide said ends along the respective upper and lower contacts to provide such movement of said ends over the respective cam surfaces.

10. The switch structure of claim 9 in which the respective upper and lower termini of said cam surfaces are positioned along a common plane, and in which the snap action of said snap contact is elfectuated by an overcenter movement thereof, such common plane defining substantially the center of movement of said snap contact.

References Cited in the file of this patent UNITED STATES PATENTS 1,819,196 Osgian Aug. 18, 1931 1,846,513 Douglas Feb. 23, 1932 2,152,450 Arcelon Mar. 28, 1939 2,526,850 Charbonneau Oct. 24, 1950 2,598,856 Swan et al. June 3, 1952 2,603,813 Christensen July 14, 1952 2,645,726 Van Ryan et al. July 14, 1953 2,648,728 Bollhoefer Aug. 11, 1953 2,786,362 Immel et al Mar. 26, 1957 2,805,298 Gebel Sept. 3, 1957 

